Microfluidic devices have gained interest as a potential avenue for increasing throughput, accuracy and automatability of chemical, biochemical and biological analyses while reducing instrument and reagent costs, space requirements, and the like. Typically, such systems employ integrated channel networks disposed in solid substrates. Analytical reagents are transported through the conduits, mixed, diluted, separated and analyzed. In their simplest forms, such channel networks merely require a network of conduits connecting the various reagent and or sample sources, as well as a material transport system for moving the various reagents through those conduits in a controlled fashion. Specifically, all that is required for basic, rudimentary function are sources of reagents, a fluid connection between those sources, a means for controllably moving those reagents together via that fluid connection, and a detection or analysis system for analyzing those reagents.
While the design and operation of many microfluidic devices and systems can appear elegant in its simplicity, in order to maximize their benefit, these devices and systems should be optimized for the particular analytical operation for which they are intended. Specifically, mere fabrication of interconnected channels into a substrate may provide one with an ability to perform a desired operation, e.g., reaction or separation. However, that operation is more than likely to be running under sub-optimal conditions. In particular, most channel network design to date in microfluidics has simply focused upon getting a reagent from a first location to a second location without analyzing and/or optimizing for how that transport is carried out.
As can be seen from the foregoing, there exists a profound need for methods for designing microfluidic channel networks, which methods optimize for the analytical operation that is to be carried out. The present invention meets these and a variety of other needs.
In a first aspect, the present invention provides a method of designing a channel network for a microfluidic device for performing a given analysis. The method comprises selecting a driving force for moving fluid materials through said microfluidic device. At least one reaction is identified for the given analysis. A channel network is designed that performs the given analysis using the driving force. The channel network comprises at least first, second and third channel segments. The second and third channel segments intersect and are in fluid communication with the first channel segment. The designing comprises providing first, second and third lengths for the first, second and third channel segments, respectively, and at least a first cross-sectional dimension for each of the first, second and third channel segments. The first, second and third lengths and at least one cross-sectional dimension are substantially optimized for the at least one reaction requirement.
A further aspect of the present invention is a method of designing a channel network for a microfluidic device for performing a given analysis. At least first, second and third parameters of said analysis are identified. A driving force is selected for moving fluid reagents through the channel network for performing the analysis. A channel network is then designed for use with the driving force to perform the given analysis while operating within the first, second, and third parameters.
Another aspect of the present invention is a computer implemented process for designing channel networks for performing a desired analytical operation. A selected driving force is input into a computer to be used in performing the analytical operation of at least one reaction requirement. The computer comprises appropriate programming for calculating first, second and third lengths for first, second and third interconnected channel segments, and at least one cross-sectional dimension of the first, second and third channel segments. The first, second and third lengths and the at least one cross-sectional dimension are substantially optimized for the at least one reaction requirement in performing the analytical operation.